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Gunman fired 31 times in Ariz. shooting

From NBC's Pete Williams Investigators say 31 shell casings were recovered from the scene of Saturday's shooting. That means, they say, that Jared Loughner fired 31 times. They say he had a 30-round magazine on his Glock-19, plus one round in the chamber, for a total of 31 rounds on the weapon. Of the 31 rounds, 20 struck those present -- killing six and wounding 14.

It's not entirely clear whether Loughner was able to put the second magazine into the Glock to continue shooting. An examination of the second magazine shows that its spring was defective, so it would not have functioned properly. But witnesses have said they grabbed the magazine as he tried to load it.